Coating for metallic chills



(Nb Model.)

H. A. HO'WE. Coating lfoi"v MetallV chills. Paten-ted Feb. 1,1881.

7.7/1 Venier: Herzig/JA jg-FWB N. PETERS, PHOTO-Ln HOGRAFHER. wASHlNGT UNITED STATES PATENT GEEICE.

HENRY A.` HOWE, OF DETROIT, MICHIGAN.

`COATING" FOR METALLIC CHI-LLS.

SPECIFIATION forming part of Letters Patent No. 237,281, dated February 1, 1881.

' Applcationled October 23, 1880. (No model.) v

To all 'whom it'may concern:

Be it known that I, HENRY ARCHIBALD HOWE, of the city of Detroit, in the county of Wayne and State of Michigan, one of the United States of America, gentleman, have invented certain new and useful Improvements in a Coating for Metallic Ohills; and I do declare that the following is a full, clear, and exact description of the same.

My invention relates to improvements in coating metallic chills, whereby a castingprovided with'h'oles having parallel sides may be formed by means of a chill havingparallel sides; andfto4 this end the improved coating to be applied: to the outer surface of the chill consists of AVffpetroleum or oleaginous matter covered by plunibago, as hereinafter more fully set forth. f;

The greatest utility of coating will be found in casting pulleys, wheels. and other similar articles, suchsas are compelled to be bored out true to t upon or run on shafts or axles, for by the application of this coating to the outer `surface of sa, chill with parallel sides a perfectly vtrue hole, perfectly straight, and with paralled sides, and smooth enough to run upon a shaft or Vfarle, can readily and easily be obtained, thereby avoiding the expense and trouble of boring, while at the same time all the benefits derived from a chilled surface will be had.

The figure is a vertical central section through a wheel moldedin the sand, with the core-chill in place, resting in the sand-core prints.

In the accompanying drawing, which forms a part of this specification, A represents a round, straight steel shaft or core-chill, with` parallel sides of that portion ofit from a to b, which is designed for chilling` purposes. This portion of the chill is prepared for use by thinly and evenly being coated with petroleu in or oleaginous matter, to which is applied thinly and evenly a coating of plumbago which has been pnlverized to an almostimpalpable powder.

The wheel B is moldedin the ordinary manner, and after the pattern is removed from the sand the core-chill is placed in the sand-core prints. If it is desired that the ends of the hub of the wheel be even and true, the corechill may be provided with iianges c, one of which may be rigidly secured to the chill, and the other may be in the form of a ring to slip onto the chill for convenience in adjusting it, or both flanges may be removable.

After the casting is poured in the usual way, in cooling the iron shrinks, and were it not for the coatings on the core-chill the iron would so closely embrace it that it could not be withdrawn, nor could the shaft or chill be rotated; but the heat of the iron slowly decomposes the petroleum, which is prevented from burning by the intervening coating of plumbago, which latter leaves a smooth surface on the chilled iron, the two coatings forming a cushion to prevent the cooling iron from so thoroughly embracing the core-chill that it may not be easily and readily removed.

It will be observed that a coat or layer of the petroleum is first applied to the chill, and that a layer or coat of plumbago is afterward applied to the chill over the petroleum, which I prefer to a compound of the petroleum and plumbago.

What I claim as my invention is- 1. A coating for metallic chills, consisting of petroleum or oleaginous matter covered with a layer of plumbago, as and for the purpose set forth.

` 2. A chill with paralled sides coated with petroleum or oleaginous matter and a superposed layer of plumbago, substantially as described, and for the purpose set forth.

HENRY A. HOWE. Witnesses:

CHARLES J. HUNT, H. S. SPRAGUE. 

